Self-lubricating catheter

ABSTRACT

A urinary catheter provided with a lubrication lumen extending from an eye adjacent the distal tip to a reservoir adjacent the drainage funnel, with means for permitting, causing and controlling the flow of lubricant from the reservoir to the eye as the catheter is inserted into a patient.

United States Patent [1 1 Norton et al.

[ SELF-LUBRICATING CATHETER [75] Inventors: William J. Norton, BerkeleyHeights; Keith Ferguson, Ruther- ,[21] Appl. No.: 205,827

[ n 3,726,281 51 Apr. 10, 1973 Primary Examiner-Charles F. RosenbaumAtt0rneyW. Saxton Seward [57] ABSTRACT I A urinary catheter providedwith a lubrication lumen [52] US. Cl. ..128/349 R extending from an eyeadjacent the distal tip to a [5 Clreservoir adjacent e ge u e means forFleld of Search p g, causing and controlling the flow of lubri cant fromthe reservoir to the eye as the catheter is inserted into a patient.[56] References Cited 8 Claims, 3 Drawing Figures UNITED STATES PATENTS2,845,930 8/l958 Brown 128/348 PATENTED 1973 FIG. 1

INVENTORS WILLIAM J. NORTON FERGUSON SELF-LUBRICATING CATHETERBACKGROUND OF THE INVENTION In medical procedures which utilize urinarycatheters it is often necessary or desirable to lubricate the catheterbefore it is inserted into the body. At thepresent time there are twobasic procedures to provide catheter lubrication.

In thefirst method a packet of sterile lubricant is torn open and thecontent is squeezed onto the catheter surface. When the lubricant isapplied to the catheter surface it becomes very awkward to handle bothobjects and properly place the lubricant while maintaining sterileconditions. After the lubricant is placed on the catheter tip, the areanear the tip of the catheter must be grasped with a gloved hand to pushthe catheter into the urethra until it reaches the bladder. It is oftendifficult to get a satisfactory grip on the lubricated surface of thecatheter.

The second procedure utilizes lubricant in a syringe. The lubricant isinjected into the urethra before insertion of the catheter. This methodinvolves the risk of forcing excessive quantities of lubricant up intothe bladder where it may not be easily expelled. The excess lubricant inthe bladder can, in time, harden with calcium deposits and become asource of extreme discomfort.

Alternative efforts to solve the problem of catheter lubrication arerepresented by the Walck et al. U.S. Pat. No. 3,556,294 and thereferences cited therein, namely, Vitello, U.S. Pat. No. 3,545,988 andSheridan U.S. Pat. No. 3,169,527.

The present invention eliminates the need for additional materials andhandling. The invention is a single use disposable unit which allows aminimum amount of lubricant to be released from the tip of the catheteras it is advanced into the body and along the length of the urethra. Thesurface of the catheter outside the body remains dry and easily graspedto push the catheter forward up into the bladder. Lubricant which hasbeen pushed back at the entrance of the urethra during the initialcatheter insertion serves to lubricate the catheter surface further backalong the length of the catheter as it enters the urethra. The dischargeof the lubricant from its reservoir is controlled by releasing a clampand applying pressure to the reservoir as lubricant is needed. When thecatheter is fully inserted, the reservoir may again be clamped off andany remaining lubricant can be left within the reservoir to be discardedwith the catheter when it is withdrawn from the patient.

In order to manufacture a self-lubricating Foley catheter a standardirrigation Foley catheter with three separate lumens is modified in thefollowing manner. First, a small flow restraining orifice is insertedinto the irrigation funnel arm of the catheter. Without this oriflee thelubricant would be expelled in too short a time period to allow controlof the lubricant during the time required for complete insertion of thecatheter. A clamp is positioned immediately behind the orifice at thefunnel end of the irrigation arm and a valve is fitted in the end of thefunnel. The chamber formed between the clamp and the valve can thusserve as a reservoir for the lubricant. After the assembly is complete,the reservoir is filled with three to five cubic centimeters oflubricant. The lubricant filled unit is then. placed into an autoclavewhere the lubricant is sterilized. The entire unit is then packaged andgas sterilized as a readyto-use product.

A practical embodiment of the invention is shown in the accompanyingdrawing, wherein:

FIG. 1 represents an elevation of the catheter, parts being broken awayand parts being shown in section.

FIG. 2 represents an enlarged axial section of the distal end of thecatheter, and

FIG. 3 represents an enlarged elevation of the flow restrainer.

Referring to the drawing, the catheter 10 is basically a three-lumenFoley irrigation and drainage catheter, having a drainage lumen 11communicating with the eye 12 adjacent the distal tip 13 and terminatingproximally in the funnel 14. The inflation lumen 15 communicates at 16with the interior of the balloon l7 and terminates proximally in theinflation funnel 18 which may be open, as shown, or may be closed by avalve such as that shown in Garth U.S. Pat. No. 3,087,492.

The third lumen 19 extends from the eye 20, located as close aspracticable to the tip 13 of the catheter, to the funnel 21 which isclosed proximally by a Gilbert plug 22 of self-sealing material (orequivalent closure) and is also equipped with a lubricant flowrestrainer 23, securely lodged in the lumen at approximately the pointwhere the funnel 21 attains its least diameter. The flow restrainer 23is a cylindrical .body having a reduced diameter outer surface zone 24spaced from both ends and being traversed by a small axial bore 25, thesize of which is related empirically to the viscosity of the lubricantto be used and to the compression of the lubricant within the funnel.

The catheter constructed as just described is loaded with a suitablequantity of lubricant (normally a geltype material) by means of a needleinserted through the plug 22. With the clamp 26 applied proximally ofthe flow restrainer 23 the lubricant is forced in to fill the chamberbetween plug 22 and clamp 26, stretching the funnel somewhat, asindicated in FIG. 1. The total quantity of lubricant may suitably be onthe order of 3 to See. If desired, the funnel may be filled initiallywithout stretching while air is permitted to escape through the lumen19, the clamp 26 being then applied and additional lubricant forced inunder pressure.

As noted above, the filled unit is autoclaved to sterilize the lubricantand the unit is then packaged and gas sterilized.

An added feature of this catheter is that it can be enclosed within aclear plastic sleeve before packaging to provide the user with acatheter which can be lubricated and administered to the patient whileenclosed in a sterile sleeve from the time it is removed from thepackage to the time it is inserted and in place within the patient. Thesleeve is removed and discarded after the catheter insertion iscompleted. This new procedure which is made possible by the provision ofa prelubricated catheter enclosed in a plastic sleeve will reduce theincidence of infection resulting from unsterile insertion procedures andwill reduce the time and extra caution now required for catheterinsertion.

The catheter with the self-lubricating feature used without the sleeveoffers three distinct advantages over what is currently available.First, the handling is minimized by not requiring the lubricant to beopened and placed on the catheter while trying to maintain sterileconditions. Second, the lubricated catheter can be grasped on a drysurface for insertion. Third, the amount of lubricant can be controlled,which reduces the risk of allowing excess amounts of lubricant to bepushed up into the bladder.

While an embodiment of the invention is shown and described inconnection with a Foley (balloon) catheter it will be appreciated that asingle lumen catheter could be made self-lubricating in the same mannerby forming it with a lubrication system corresponding to the elements19-26, the balloon system -18 being omitted. Although described in termsof a urinary catheter, the lubrication system could be adapted to othertypes of catheters wherever lubrication during insertion is recommended.With the provision of sufficient capacity in the lubricant reservoirchamber, as by enlarging the funnel 21, the pre-com pression featurecould be eliminated, leaving it to the operator to squeeze out thelubricant at any desired rate, but preferably still under the control ofthe flow restrainer. The entire catheter may be of rubber latex, formedby dipping in the usual manner, or the shaft may be an extruded plasticwith separately formed rubber or plastic funnels and balloon, if any.The flow restrainer 23 is of any suitable relatively solid plastic.

It is further contemplated that the elements 19,20,21, 22, 26 and 23 (ifneeded) may be formed as a small separate lubricating cannula, insertedinitially within the drainage lumen of a plain or foley catheter, withan eye (corresponding to eye in register with or adjacent the drainageeye (such as 12), the lubricant being expressed through said eyes duringinsertion of the catheter and the lubricating cannula being thereafterremoved and discarded.

What we claim is:

1.. A catheter adapted for insertion into a body passage of restrictedsize comprising a shaft, a main lumen traversing said shaft from a pointadjacent the distal tip thereof to the proximal end thereof, and anintegral lubrication system including an eye close to the distal tip ofthe catheter, a funnel adjacent the proximal end of the catheter, alumen connecting said funnel to said eye, a first closure for theproximal end of said funnel and a removable second closure for thedistal end of said funnel, the interior of said funnel between saidclosures constituting a lubricant containing chamber from whichlubricant may be expressed upon removal of the removable closure.

2. A catheter according to claim 1 which includes a flow restrainer insaid second named lumen adjacent the connection thereof to said funnel.

3. A catheter according to claim 2 wherein the flow restrainer is acylindrical body traversed axially by an orifice smaller than thecross-section of said lumen.

4. A catheter according to claim 1 in which the first closure is aone-way valve.

5. A catheter according to claim 4 in which the valve is a plug ofself-sealing material.

6. A catheter according to claim 1 in which the second closure is aclamp.

7. A catheter according to claim 1 in which said funnel is adapted to beinflated by forcible injection of lubricant, to restrain the lubricantunder pressure and to express automatically a portion of the lubricantupon removal of said second closure. I

8. A catheter according to claim 1 WlllCh includes a quantity oflubricant confined in the funnel, the funnel being stretched and thelubricant being under pressure.

1. A catheter adapted for insertion into a body passage of restrictedsize comprising a shaft, a main lumen traversing said shaft from a pointadjacent the distal tip thereof to the proximal end thereof, and anintegral lubrication system including an eye close to the distal tip ofthe catheter, a funnel adjacent the proximal end of the catheter, alumen connecting said funnel to said eye, a first closure for theproximal end of said funnel and a removable second closure for thedistal end of said funnel, the interior of said funnel between saidclosures constituting a lubricant containing chamber from whichlubricant may be expressed upon removal of the removable closure.
 2. Acatheter according to claim 1 which includes a flow restrainer in saidsecond named lumen adjacent the connection thereof to said funnel.
 3. Acatheter according to claim 2 wherein the flow restrainer is acylindrical body traversed axially by an orifice smaller than thecross-section of said lumen.
 4. A catheter according to claim 1 in whichthe first closure is a one-way valve.
 5. A catheter according to claim 4in which the valve is a plug of self-sealing material.
 6. A catheteraccording to claim 1 in which the second closure is a clamp.
 7. Acatheter according to claim 1 in which said funnel is adapted to beinflated by forcible injection of lubricant, to restrain the lubricantunder pressure and to express automatically a portion of the lubricantupon removal of said second closure.
 8. A catheter according to claim 1which includes a quantity of lubricant confined in the funnel, thefunnel being stretched and the lubricant being under pressure.